Light oil reserves are gradually being depleted and the cost to develop, such as lifting, mining and extracting, heavy oil resources is increasing, and thus a growing need arises to explore new upgrading technologies that can convert heavy oils and bitumen into lighter, usable products.
Heavy hydrocarbon oils are generally referred to as oils with high viscosity or an API gravity less than about 23 degree. Large quantities of such heavy hydrocarbon oils are available in oil deposits in Western Canada and heavy bituminous oils extracted from oil sands. Other sources of heavy hydrocarbon oils can be materials such as atmospheric tar bottoms products, vacuum tar bottoms products, heavy cycle oils, shale oils, coal-derived liquids, crude oil residue, topped crude oils, and combinations thereof.
Efficient processing and viscosity reduction of heavy hydrocarbon oils is desirable for the production, transport and refining operations of crude oil. A drawback of known methods of treating heavy hydrocarbon oils is that the viscosity reduction effect is reversible such that the reduced viscosity of the heavy oil recovers back towards the original viscosity. Further, changes in the API gravity are less than 2 units and in some cases no change in API gravity is detected. Accordingly, it is desirable to develop an efficient process for upgrading heavy hydrocarbon oils wherein the viscosity reduction is stable subsequent to processing and a significant change in API gravity of the oil is realized.